1. Field of the Invention
This invention generally relates to wireless communications antennas and, more particularly, to a tri-band antenna that resonates at three non-harmonically related frequencies.
2. Related Art
The size of wireless communications devices, such as wireless telephones, continues to shrink, even as users demand more functionality. One consequence of this tension between size and function is the pressure for manufactures to make smaller antennas. This pressure is compounded if the wireless device is expected to operate in a plurality of frequency ranges. Many wireless telephones, for example, are expected to operate in the cellular band of 824 to 894 megahertz (MHz), the PCS band of 1850 to 1990 MHz, and to receive global positioning satellite (GPS) signals in the band of 1565 to 1585 MHz. Other telephonic devices are also expected to operate in the Bluetooth band of 2400 to 2480 MHz.
It would be advantageous if a small microstrip antenna could be designed to resonate at three distinct non-harmonically related frequencies.
It would be advantageous if the above-mentioned microstrip antenna could be designed to operate in the cellular, GPS, and PCS bands.